This disclosure relates generally to online systems, and in particular to presentation of advertisements to users of an online system.
An online system allows its users to connect to and communicate with other online system users. Users may create profiles on an online system that are tied to their identities and include information about the users, such as interests and demographic information. The users may be individuals or entities such as corporations or charities. Because of the increasing popularity of online systems and the increasing amount of user-specific information maintained by social networking systems, such as a social networking system, an online system provides an ideal forum for advertisers to increase awareness about products or services by presenting ads to online system users.
Presenting advertisements to users of an online system allows an advertiser to gain public attention for products or services and to persuade online system users to take an action regarding the advertiser's products, services, opinions, or causes. Many online systems generate revenue by displaying advertisements to their users. Frequently, online systems charge advertisers for each presentation of an advertisement to an online system user (i.e., each “impression” of the advertisement) or interaction with an advertisement by an online system user.
Advertisers, such as mobile application developers, may seek to present advertisements to online system users likely to be interested in an advertised product or service via the online system. For example, users of a game application who have reached a certain level in the game may be more likely to be interested in an advertisement about new levels added to the game than users that are unfamiliar with the game. Conventionally, to identify relevant advertisements for presentation to various users of an online system, developers of third-party applications collect data about their users and select advertisements for particular users based on the collected data. However, this method of advertisement selection requires third-party application developers or advertisers to access information maintained by an online system that associates the identities of third-party application users with users of the online system.
By allowing advertisers to access information that identifies online system users, an online system risks exposing a user's personal information to advertisers that are otherwise unable to access such information; information that online system users entrust to the online system. This potential exposure threatens an online system user's privacy. Because users often distrust companies that risk the privacy of their information, and because of laws that governing privacy of user information, online systems need to balance protection of user identifying information with allowing advertisers to leverage certain information to provide targeted advertisements.